Sökning: "emissivity effect"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden emissivity effect.

  1. 1. Chemical Vapor Depositionof Si and SiGe Films for High-Speed Bipolar Transistors

    Författare :Johan Pejnefors; KTH; []
    Nyckelord :chemical vapor deposition CVD ; bipolar junction transistor BJT ; heterojunction bipolar transistor HBT ; silicon-germanium SiGe ; epitaxy; poly-Si emitter; in situ doping; non-selective epitaxy NSEG ; loading effect; emissivity effect;

    Sammanfattning : This thesis deals with the main aspects in chemical vapordeposition (CVD) of silicon (Si) and silicon-germanium (Si1-xGex) films for high-speed bipolar transistors.In situdoping of polycrystalline silicon (poly-Si)using phosphine (PH3) and disilane (Si2H6) in a low-pressure CVD reactor was investigated toestablish a poly-Si emitter fabrication process. LÄS MER

  2. 2. Study of Collimated Neutron Flux Monitors for MAST and MAST Upgrade

    Författare :Siriyaporn Sangaroon; Göran Ericsson; Marco Cecconello; Matthias Weiszflog; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fusion; Plasma diagnostics; Neutron camera; collimated neutron flux monitor; MAST; MAST Upgrade; ITER; Applied Nuclear Physics; Tillämpad kärnfysik;

    Sammanfattning : Measurements of the neutron emission, resulting from nuclear fusion reactions between the hydrogen isotopes deuterium and tritium, can provide a wealth of information on the confinement properties of fusion plasmas and how these are affected by Magneto-Hydro-Dynamic (MHD) instabilities.This thesis describes work aimed to develop neutron measurement techniques for nuclear fusion plasma experiments, specifically regarding the performance and design of collimated neutron flux monitors (neutron cameras) for the Mega Ampere Spherical Tokamak, MAST, and for MAST Upgrade. LÄS MER

  3. 3. Experimental studies of confinement in the EXTRAP T2 and T2R reversed field pinches

    Författare :Marco Cecconello; KTH; []
    Nyckelord :extap t2; extrap t2r; reversed field pinch; NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : The confinement properties of fusion plasmas are affected bymagnetic and electrostatic fluctuations. The determination ofthe plasma confinement properties requires the measurement ofseveral global and local quantities such as the ion andelectron temperatures, the electron and neutral densityprofiles, the radiation emissivity profiles, the ohmic inputpower and the particle and heat diffusivities. LÄS MER

  4. 4. Visible spectroscopic diagnostics : application and development in fusion plasmas

    Författare :Sheena Menmuir; Professor Elisabeth Rachlew-Källne; Lorella Carraro; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; visible spectroscopy; fusion; Doppler shift; Doppler broadening; Plasma physics with fusion; Plasmafysik med fusion;

    Sammanfattning : Diagnostic measurements play a vital role in experiments. Without them we would be in the dark with no way of knowing what was happening; of understanding the processes and behaviour occurring; or even of judging the success or failure of our experiments. The development of fusion plasma devices is no different. LÄS MER

  5. 5. Experimental methods of neutron diagnostics and fast ion physics for fusion devices

    Författare :Andrea Sperduti; Marco Cecconello; Massimo Nocente; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik med inriktning mot tillämpad kärnfysik; Physics with specialization in Applied Nuclear Physics;

    Sammanfattning : Measurements of the neutron emission resulting from nuclear fusion reactions provide an abundance of information on the underlying spatial, temporal and energetic distributions of reacting ions and how they are affected by a wide range of MagnetoHydroDynamic (MHD) instabilities.This thesis focuses on studies of the neutron emission and fast ion physics at the Mega Ampere Spherical Tokamak (MAST), its upgrade MAST-U, the Joint European Torus (JET) and the Divertor Tokamak Test (DTT). LÄS MER